This is the fourth of a series of miscellaneous contributions, by various authors, where hitherto unpublished data relevant to both the Med-Checklist and the Euro Med (or Sisyphus) projects are presented. This instalment deals with the families Amaranthaceae, Asclepiadaceae, Boraginaceae, Caryophyllaceae, Compositae, Cruciferae, Euphorbiaceae, Guttiferae, Malvaceae, Onagraceae, Orobanchaceae, Portulacaceae, Rosaceae; Commelinaceae, Gramineae, Liliaceae and Palmae. It includes new country and area records, taxonomic and distributional considerations for taxa in Amaranthus, Cardamine, Cerastium, Commelina, Euphorbia, Hieracium, Hypericum, Lilium, Melinis, Myosotis, Oenothera, Orobanche, Portulaca, Pyrus, Rubus, Senecio, Silene, Sporobolus, Tulipa, Vincetoxicum and Washingtonia, the validation of names in Malva and Polycarpon, and a corrigendum to an entry for Pilosella in the previous instalment.